IssueTracker

Navigation is built with Support Library Fragments so has no access to the FragmentFactory itself. I think we can make some minor changes to FragmentNavigator to make it easy for developers who are using Navigation 1.0 and Fragments 1.1.0 together to call through to their FragmentFactory.

Once Navigation switches to AndroidX (post 1.0), we'll use FragmentFactory directly.

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 1b215f0d93828286782776b9a12d2387097947f9
Author: Ian Lake <ilake@google.com>
Date:   Sun Nov 25 21:45:56 2018

    Move Fragment creation to FragmentNavigator
   
    Provide an instantiateFragment() method on
    FragmentNavigator which serves as the
    centralized place to instantiate new
    Fragment instances for FragmentNavigator.
   
    Besides moving this business logic out of
    the dumb POJO FragmentNavigator.Destination,
    this also provides a future extension point
    for integrating in FragmentFactory.
   
    Test: existing tests passes, testapp still works
    BUG: 119054429
    Change-Id: If60471a704ef77bc35b30838e152a31cde8bc235

M       navigation/fragment/ktx/src/androidTest/java/androidx/navigation/fragment/FragmentNavigatorDestinationBuilderTest.kt
M       navigation/fragment/ktx/src/main/java/androidx/navigation/fragment/FragmentNavigatorDestinationBuilder.kt
M       navigation/fragment/src/androidTest/java/androidx/navigation/fragment/FragmentNavigatorTest.kt
M       navigation/fragment/src/main/java/androidx/navigation/fragment/FragmentNavigator.java

https://android-review.googlesource.com/835682
https://goto.google.com/android-sha1/1b215f0d93828286782776b9a12d2387097947f9

Navigation still depends on Support Library and not AndroidX, so we can't directly use FragmentFactory in FragmentNavigator.

However, in alpha08, you'll be able to subclass FragmentNavigator and override instantiateFragment(), calling into FragmentFactory if you're using AndroidX Fragment 1.1.0+. You'd also need to subclass NavHostFragment and override createFragmentNavigator() to return your custom FragmentNavigator subclass (or, if you're not using app:navGraph, you can set it via navHostFragment.navController.navigatorProvider += YourFragmentNavigator(context, navHostFragment.childFragmentManager)).

We'll keep this open until Navigation has moved to AndroidX and can directly use FragmentFactory as its default implementation of instantiateFragment().

Thanks for the workaround in alpha08!